Delta Wye Motor with no name plate.

Saturn_Europa

Saturn_Europa

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Fishing Industry
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Electrician Limited License NC, QMED Electrician
The name plate is not really legible. But I can make out the KW and 480v. I want to wire this 480. On a 6 lead IEC, the high voltage is always Y?

I plan to wire it in Y, by moving the shorting bars to W2, U2, and V2. Then bringing my leads to U1 and V2 and W2. Does this sound correct?


Really wish everything in life was a 9 lead dual voltage motor.
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If it is rated 480 volts when wye connected then it would have to be 277 rated when delta connected so 240 is a little on the low side and 208 would be even lower. 277 not a common three phase voltage so probably not likely intended to be connected for that.

If it were 415 volts rated when wye connected like they are when used in European countries then it would be 240 rated when connected in delta. But this appears to be rated 60 Hz so that probably not what it was intended for.

It likely is same motor design as for European 415 volts @ 50 Hz, which if you ran it on 480 volts @ 60Hz, you have approximately same V/F ratio and won't have saturation issues in windings because of wrong V/F ratio, but will also run at higher speed than 50 Hz. Since it is marked 60 (presuming that is the frequency) and 1720 (which is in proper range for a 4 pole wound motor at 60 Hz) that is my best guess of what this likely is and they likely do use same build for the 50Hz world but mark it with appropriate data for when it is supplied with 50 Hz.

The wye connection is likely only intended for wye-delta starting methods though you don't really see that done in North America with that small of a motor.
 
infinity said:
He's wiring it with 480.
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I got that, but he also mentioned he planned to connect it "Wye". Which I guess wouldn't be as damaging as connecting something rated for 240 input to 480 volts. This motor should need about 830 volts input to run at nameplate rating if wye connected, if it is wound the way I think it is.
 
kwired said:
I got that, but he also mentioned he planned to connect it "Wye". Which I guess wouldn't be as damaging as connecting something rated for 240 input to 480 volts. This motor should need about 830 volts input to run at nameplate rating if wye connected, if it is wound the way I think it is.
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I don't think so. With a wye, the voltage the windings see is reduced by the square root of 3. The windings see the full applied voltage when connected in delta. For this type of motor, the delta connection is always the low voltage connection. The OP says he sees a 480 volt nameplate rating on this motor, which is unusual. If the 480 volts on the name plate is the low voltage for that motor, then the high voltage should 831 volts, and I don't think that is a common voltage anywhere.
 
don_resqcapt19 said:
I don't think so. With a wye, the voltage the windings see is reduced by the square root of 3. The windings see the full applied voltage when connected in delta. For this type of motor, the delta connection is always the low voltage connection. The OP says he sees a 480 volt nameplate rating on this motor, which is unusual. If the 480 volts on the name plate is the low voltage for that motor, then the high voltage should 831 volts, and I don't think that is a common voltage anywhere.
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If delta is the 480 volt connection then you would need to supply it with 830 volts if you connected it in wye in order to have 480 across each winding. That's why I think the only intention for connecting it in wye would be for wye-delta starting method. Otherwise if it were intended to be dual volts with 480 as the high voltage then for low voltage you would need 277 volt three phase which is also not a common three phase voltage and connect it in the delta configuration.
 
kwired said:
If delta is the 480 volt connection then you would need to supply it with 830 volts if you connected it in wye in order to have 480 across each winding. That's why I think the only intention for connecting it in wye would be for wye-delta starting method. Otherwise if it were intended to be dual volts with 480 as the high voltage then for low voltage you would need 277 volt three phase which is also not a common three phase voltage and connect it in the delta configuration.
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I think this is really a IEC motor with a nameplate for the US and the actual motor voltage is 400/230.
 
don_resqcapt19 said:
I think this is really a IEC motor with a nameplate for the US and the actual motor voltage is 400/230.
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I been trying to say that, it works on 60 Hz @ 480 volts because it is still same V/F ratio, will have higher speed and higher power rating than when run @50 Hz, still draws same amps when fully loaded at either volts/frequency.
 
kwired said:
I been trying to say that, it works on 60 Hz @ 480 volts because it is still same V/F ratio, will have higher speed and higher power rating than when run @50 Hz, still draws same amps when fully loaded at either volts/frequency.
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But if it is an IEC motor then you connect in wye for 400 volts and delta for 230 volts, so the connection for 480 volts will be wye.
 
don_resqcapt19 said:
But if it is an IEC motor then you connect in wye for 400 volts and delta for 230 volts, so the connection for 480 volts will be wye.
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Is same motor design, just has a nameplate with information for use in the 60Hz portion of the world.

If this wasn't a motor built in (most likely) a place in the 50Hz portion of the world they wouldn't build it with six leads unless other than if they intended it to be possible to be started with wye-delta methods. But that not all that common with this small of a motor to start them that way. Have to get bigger than say 50 HP before you start to see more of that possibility, at least in North America.
 
I got ahold of the maintenance staff of the facility that this unit came out off. It was wired delta at 480v when it was removed. I ended up wiring it delta just as the first pictures show. Amps are high (15.5A), but it runs fine.
 
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Saturn_Europa said:
I got ahold of the maintenance staff of the facility that this unit came out off. It was wired delta at 480v when it was removed. I ended up wiring it delta just as the first pictures show. Amps are high (15.5A), but it runs fine.
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High amps is likely driven load related issue and not a problem with the motor. Too low of supply voltage also a possibility.
 
You could try strapping it for Wye To reduce the amp draw, and then test it to see if it still has enough HP for the job it is tasked with.
What is the overload relay set up for? But it seems strange that the tag re-make was stamped with the Delta symbol. Might be that they needed the extra power and the load use is intermittent?
 
MTW said:
You could try strapping it for Wye To reduce the amp draw, and then test it to see if it still has enough HP for the job it is tasked with.
What is the overload relay set up for? But it seems strange that the tag re-make was stamped with the Delta symbol. Might be that they needed the extra power and the load use is intermittent?
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If it’s maxed out (or more) load-wise, wiring it wye and connecting to the same voltage won’t help at all. It will be even more under-powered.
 
MTW said:
You could try strapping it for Wye To reduce the amp draw, and then test it to see if it still has enough HP for the job it is tasked with.
What is the overload relay set up for? But it seems strange that the tag re-make was stamped with the Delta symbol. Might be that they needed the extra power and the load use is intermittent?
Click to expand...
If there is too much demand from the driven load, hooking it up in wye configuration should only make things worse as each winding will now see ~277 volts instead of 480 yet the frequency and number of poles is the same so it is going to attempt to try to run at same speed even though it will have less voltage applied, current has to go up in order to get it done. Depending on situation it may not be able to go up enough to reach design speed but will definitely heat things up whether it gets there or not.
retirede said:
If it’s maxed out (or more) load-wise, wiring it wye and connecting to the same voltage won’t help at all. It will be even more under-powered.
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I thought I posted that, then I see I must have never hit the post reply button as my reply was still there :oops:
 
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